Field of the Invention
The present invention relates to piezoelectric transformers, and more particularly to a piezoelectric transformer with multiple outputs comprising a plurality of output terminals in a fluorescent lamps stabilizer, which supplies stable voltages to more than two fluorescent lamps without a ballast capacitor.
Generally, a fluorescent lamp, which is a sort of a discharge tube, requires a high voltage at primary lighting in order to emit thermal electrons for an electric discharge. After electric discharge, a voltage supplied to a fluorescent lamp decreases according to an increment of current. Namely, the voltage has a negative resistance characteristic.
A stabilizer of fluorescent lamp, which is a lighting lamp device, supplies a high voltage to the fluorescent lamp with the characteristic above for lighting the lamp at primary time, and keeps a regular luminosity by controlling a current of the lamp after the lighting.
Referring to FIG. 6, FIG. 6 illustrates a general block diagram of configuration of a stabilizer of fluorescent lamp. As shown in FIG. 6, A fluorescent lamp stabilizer comprises a rectifying section 621 for rectifying from AC commercial supply voltage 61 into a DC voltage of some level, a power factor compensating section 622 for compensating the power factor to the output of the rectifying section 621, which is generated by the fluctuation of the AC commercial supply voltage 61, an AC voltage generating section 623 for converting a uniform DC current inputted from the power factor compensating section 622 to AC voltage having a high frequency, and a resonating section 624 for outputting the AC voltage to the fluorescent lamp 63 by resonating the output voltage of the AC voltage generating section 623. The AC voltage generating section 623 is called a inverter.
Typically, the resonating section 624 was formed to generate a resonance by an inductance of a wound-type transformer and capacitance of the capacitor by connecting the capacitor to the wound-type transformer. However, the wound-type transformer has problems that a defective proportion is high because of the material declination of core, and confidence of the stabilizer is lower. So a piezoelectric transformer is on an increasing trend instead of a wound-type transformer currently. The example above is the case that a fluorescent lamp is connected to a stabilizer
However, in case of lighting more than two fluorescent lamps by connecting the fluorescent lamps into one stabilizer, if one of numerous fluorescent lamps is lighted, other fluorescent lamps connected to the wound-type transformer in parallel is not lighted because a lower voltage is supplied to the other fluorescent lamps by lighting the one fluorescent lamp.
Accordingly, typically FIG. 7 and FIG. 8 depict more than two fluorescent lamps connected a stabilizer. As shown in FIG. 7 and FIG. 8, each ballast capacitor (713,813) is connected between lamps (72,82) and transformers (712,812), although one of the fluorescent lamps is lighted fist, a voltage required for lighting the lamps at primary time can be supplied to other fluorescent lamps.
FIG. 7 and FIG. 8 illustrate a perspective view of a typical fluorescent lamp stabilizer with a plurality of fluorescent lamps. As shown in FIG. 7, the fluorescent lamp stabilizer for a plurality of fluorescent lamps having a piezoelectric transformer comprises a circuit section 711, which includes the rectifying section 621, the power compensating section 622, the AC voltage generating section 623, and the resonance capacitor of the resonating section 624, the piezoelectric transformer 712 of which input electrode is connected to the resonance capacitor of the circuit section 711, and a plurality of ballast capacitors 713 being connected to output electrode of the piezoelectric transformer 712 in parallel. Wherein the number of ballast capacitors is same that of lamps. Furthermore, a plurality of fluorescent lamps 72 are connected to other terminal of the plurality of ballast capacitors 713 of the stabilizer 71 respectively.
As shown in FIG. 8, the stabilizer for a plurality of fluorescent lamps having a wound-type transformer comprises a circuit section 811, which includes the rectifying section 621, the power compensating section 622, the AC voltage generating section 623, and the resonance capacitor of the resonating section 624. And the stabilizer comprises the wound-type transformer 812 of which input electrode is connected to a resonance capacitor of the circuit section 811, and a plurality of ballast capacitors 813 being connected to output electrode of the wound-type transformer 812 in parallel. Furthermore, the plurality of fluorescent lamps 82 are connected to other terminal of the plurality of ballast capacitors 713 of the stabilizer 71 respectively.
In the stabilizer above, because AC voltage supplied by the wound-type transformer 712 or the piezoelectric transformer 812 is divided equally among the plurality of fluorescent lamps via the ballast capacitor 713,813, the plurality of fluorescent lamps can be lighted at the same time. Wherein the ballast capacitor 713,813 has a high withstand voltage characteristic, and its size is also big.
Accordingly, as shown in FIG. 7 or FIG. 8, because the stabilizer needs the ballast capacitors in proportion to the number of the connected fluorescent lamp, a volume and the number of components increase, and a cost increases also.
The present invention offers a piezoelectric transformer with multiple outputs for lighting a plurality of fluorescent lamps stably without a ballast capacitor by comprising a plurality of output electrode having a regular output characteristic.
Moreover, the present invention provides a piezoelectric transformer with multiple outputs for causing a cost saving and a simple working of a stabilizer for a plurality of fluorescent lamps by comprising a plurality of output electrode having a regular output characteristic.
The present invention relates to piezoelectric transformers, and more particularly to a piezoelectric transformer with multiple outputs, which impresses stable voltages into a plurality of fluorescent lamps without a ballast capacitor in a fluorescent lamp stabilizer.
According to the present invention, the piezoelectric transformer with multiple outputs comprises a piezoelectric plate, a first input electrode being formed on the top surface of the piezoelectric plate, a second input electrode being formed on the bottom surface of the piezoelectric plate, a plurality of first output electrodes being electrically isolated from each other, which is formed by dividing the remaining portions of the top surface of the plate excluding the surface on which the first input electrode is formed, and a second output electrode formed in the remaining portions of the bottom surface of the plate excluding the surface on which the second input electrode is formed, which is disposed at a confronting position of the plurality of first output electrode.
In case of forming a stabilizer for a plurality of fluorescent lamps, the first input electrode and second input electrode are connected to a AC voltage generator of the stabilizer, the first output electrode is connected to one terminal of more than two fluorescent lamps one to one respectively, and the other terminals of the fluorescent lamps are connected to the second output electrode in parallel.
So the present invention provides a stabilizer for lighting a plurality of lamps without a ballast capacitor by supplying a regular voltage to more than two fluorescent lamps.